Natural gas import terminal here

Its 5,000 valves, 50 million pounds of steel and ship berth as big as 77 football fields — representing a $2 billion investment by Qatar Petroleum, Exxon Mobil and Conoco Phillips — have been dormant for nearly three years. The unexpected American shale fracking frenzy produced such a glut of domestic gas that the United States does not need Qatari gas anymore.

But the Golden Pass story is only beginning.

Qatar Petroleum, the state oil company, is now requesting permission to export American gas, proposing with its partner Exxon Mobil an audacious conversion of the facility to export from import. The additional estimated cost: $10 billion, if not more.

Conoco Phillips has bowed out of the export project, deciding not to double down. For Qatar Petroleum and Exxon Mobil, the retooled plan represents a grand improvisation and a plan to export a sizable share of the new American bonanza.

“Do we hope to make money out of it that we are not making today? Absolutely,” said Robert S. Franklin, president of the Exxon Mobil Gas and Power Marketing Company. “There is very significant upside in this project.”

The two companies propose to reverse some pipelines, using the existing gas storage tanks and docks and adding three enormous refrigerant plants to the complex on land now occupied by cattle grazing under a blazing sun. The plants will take American gas and cool it to minus 260 Fahrenheit, condensing it to a liquid that can be loaded on tankers and shipped to Asian, Latin American and European markets.